Hi Travis,
sorry for the strange question, but I went from pfSense to OPNsense a year ago and was looking for an integration like this.
Since the two projects are “cousins”, and OPNsense has XmlRpc, I was wondering if it would be feasible to adapt your integration to OPNsense, what’s your opinion?
I actually tried to confgure it for OPNsense but it can’t even login, I checked the xmlrpc.php code and it expects basic authentication, I expected issues on the xmlrpc calls, not on the login. 
Thanks for any suggestion on this.